It kind of depends on how many are in line ahead of you. You have to find your number on the board and fill out the release and then find a vacant table to pick up your bag. You can spend hours at the expo because there are so many vendors there, plus they give out freebees. You can buy shoes, socks, shorts, jackets, shirts, Official Marathon goodies, plus so much more. You could be out in 15 minutes if you skip the expo. We did the expo and picked up our package on Friday afternoon (the weather was nice). If you do the 5k and family races, you have to pick up stuff on Friday. If you are only doing the marathon (full or half), you can pick up your stuff on Friday or Saturday.
We went back to the expo on Saturday afternoon because we weren't able to get some of the official marathon stuff in the size we needed until then.
The expo covers the entire floor of the basketball court area. You pick up your packages on the upper floor in the back.